Half-Life and Decay Constant
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Constant used — built into this formula, no need to enter
Natural Logarithm of Two · exactLearning zone
The half-life and the decay constant describe the same decay speed in two dialects: t1/2 is the intuitive "time to halve," while λ is the per-second probability that any given nucleus decays, the natural parameter of the exponential law N = N0e^(−λt). Setting the exponential equal to one half links them through ln 2 = 0.6931471806 — a large λ means a short half-life, and vice versa.
Half-Life and Decay Constant
Where
- = Half-life
- = Decay constant
Missing one of these? Work it out first, then come back
- Half-life — Half-Life Decay, Half-Life of a Second-Order Reaction
- Decay constant — Radioactive Activity (A = λN), Arrhenius Equation